d-of-section questions a List six characteristics of all living organisms. b In which three ways do human cells differ from those of plants? c Draw a fully labelled diagram of the structure of a typical (unspecialised) animal cell and describe the function of each part.

Certainly! Below are the answers to the end-of-section questions: --- ### **a. List six characteristics of all living organisms.** 1. **Cellular Organization** - All living organisms are composed of one or more cells, which are the basic units of life. 2. **Metabolism** - They carry out chemical reactions to obtain and use energy for growth, repair, and maintenance. 3. **Homeostasis** - Living organisms maintain a stable internal environment despite changes in the external environment. 4. **Growth and Development** - They grow and develop according to specific instructions coded in their genetic material. 5. **Reproduction** - Living things can reproduce to produce new individuals, ensuring the continuation of their species. 6. **Response to Stimuli** - Organisms can respond to environmental changes or stimuli, such as light, temperature, and touch. --- ### **b. In which three ways do human cells differ from those of plants?** 1. **Presence of a Cell Wall** - **Human Cells:** Lack a cell wall; they have only a flexible cell membrane. - **Plant Cells:** Have a rigid cell wall made of cellulose, providing structural support and protection. 2. **Chloroplasts** - **Human Cells:** Do not contain chloroplasts because they do not perform photosynthesis. - **Plant Cells:** Contain chloroplasts, which enable the cells to convert sunlight into energy through photosynthesis. 3. **Vacuoles** - **Human Cells:** Typically have small, temporary vacuoles, if any. - **Plant Cells:** Possess a large central vacuole that stores water, nutrients, and waste products, and helps maintain turgor pressure. 4. **Shape and Structure** - **Human Cells:** Generally have an irregular or flexible shape. - **Plant Cells:** Usually have a fixed, rectangular shape due to the presence of the cell wall. 5. **Centrioles** - **Human Cells:** Contain centrioles, which are involved in the organization of chromosomes during cell division. - **Plant Cells:** Do not have centrioles; they use other structures to organize cell division. 6. **Plasmodesmata vs. Gap Junctions** - **Human Cells:** Communicate with neighboring cells through gap junctions. - **Plant Cells:** Use plasmodesmata, which are channels that pass through the cell walls, allowing transport and communication between adjacent cells. *(Note: While the question asks for three differences, additional points are provided for a more comprehensive understanding.)* --- ### **c. Draw a fully labelled diagram of the structure of a typical (unspecialised) animal cell and describe the function of each part.** While I cannot provide a visual diagram here, I can describe the components of a typical unspecialised animal cell and their functions. You can use this description to create a labelled diagram. #### **Components of a Typical Unspecialised Animal Cell:** 1. **Cell Membrane (Plasma Membrane)** - **Function:** Acts as a selective barrier that controls the entry and exit of substances, maintaining the cell's internal environment. 2. **Cytoplasm** - **Function:** A jelly-like substance that fills the cell, holding organelles in place and facilitating the movement of materials within the cell. 3. **Nucleus** - **Function:** Serves as the control center of the cell, housing genetic material (DNA) and regulating cellular activities. 4. **Nuclear Membrane (Nuclear Envelope)** - **Function:** Encases the nucleus, providing a barrier between the nucleus and the cytoplasm while allowing the passage of materials. 5. **Nucleolus** - **Function:** Located within the nucleus, it is responsible for the production and assembly of ribosomes. 6. **Mitochondria** - **Function:** Known as the powerhouse of the cell, they generate ATP through cellular respiration, providing energy for cellular processes. 7. **Ribosomes** - **Function:** Sites of protein synthesis, where amino acids are assembled into proteins based on genetic instructions. 8. **Endoplasmic Reticulum (ER)** - **Rough ER:** - **Function:** Studded with ribosomes; involved in protein synthesis and processing. - **Smooth ER:** - **Function:** Lacks ribosomes; involved in lipid synthesis, detoxification, and metabolism. 9. **Golgi Apparatus (Golgi Bodies)** - **Function:** Modifies, sorts, and packages proteins and lipids for storage or transport out of the cell. 10. **Lysosomes** - **Function:** Contain digestive enzymes to break down waste materials, cellular debris, and foreign invaders. 11. **Centrioles** - **Function:** Play a key role in cell division by organizing the mitotic spindle fibers that separate chromosomes. 12. **Cytoskeleton** - **Function:** A network of protein fibers (microtubules, microfilaments, and intermediate filaments) that provides structural support, maintains cell shape, and facilitates movement. 13. **Vesicles** - **Function:** Small membrane-bound sacs that transport materials within the cell and to the cell membrane for secretion. 14. **Peroxisomes** - **Function:** Break down fatty acids and detoxify harmful substances like hydrogen peroxide. #### **Suggested Diagram Structure:** 1. **Outer Boundary:** Draw a circular or irregular shape to represent the **Cell Membrane**. 2. **Central Area:** Place the **Nucleus** towards the center. 3. **Within the Nucleus:** Include the **Nucleolus**. 4. **Scattered Throughout:** Position **Mitochondria**, **Ribosomes**, **Endoplasmic Reticulum (both Rough and Smooth)**, **Golgi Apparatus**, **Lysosomes**, **Centrioles**, and other organelles within the **Cytoplasm**. 5. **Cytoskeleton Elements:** Represented as network lines connecting different parts of the cell. *For a visual representation, consider consulting biology textbooks or reputable online resources that provide detailed diagrams of animal cells. These can aid in understanding the spatial arrangement and relationships between different cell components.* --- Feel free to ask if you need further clarification on any of these topics!